Fluid system with self cleaning filter



United States Patent 2,044,096 6/1936 Moran Inventor Appl. No.

Filed Patented Assignee Nils 0. Rosaen Bloomfield Hills, Michigan 713,018

March 14, 1968 Continuation-impart of Ser. No. 539,863,

April 4, 1966, now Patent No. 3,425,557,

which is a continuation-in-part of Ser. No.

661,968, Aug. 21, 1967, now Patent No. 3,425,558.

Nov. 24, 1970 Universal Filters Inc.

Hazel Park, Michigan a corporation of Michigan. by direct and theme assignments FLUID SYSTEM WITH SELF CLEANING FILTER 39 Claims, 10 Drawing Figs.

.U.S. Cl. 2101108, 210/120,210/171,210/257, 210/333, 210/408,

lnt.Cl. .L B0111 35/12 Field of Search 210/ 108,

333, Dig., 408,412, 497,171, 90, 95,120,134, 137,195, 232, 252, 259, 257, 258, 484, 495, 393

References Cited UNITED STATES PATENTS 2,077,589 4/1937 Seaver et a1. 210/333X 3,334,746 8/1967 'Rosaen 210/108 1,212,978 1/1917 Malone 210/393 Primary Examiner-Reuben Friedman Assistant Examiner- F rank A. Spear, Jr. Attorney-Hauke, Gifford and Patalidis ABSTRACT: A fluid system with a self-cleaning filter device having means for automatically exchanging a clogged filter element with a clean filter element without interrupting the fluid flow in the system. The filter device includes a housing having an internal chamber, and a generally planar partition member with vane means engaging the sidewalls of the chamber rotatably mounted in the chamber between a pair of rotated positions 180 apart to subdivide the chamber into a pair of subchambers. One of the subchambers is fluidly connected with the system for receiving unfiltered fluid and for discharging filtered fluid. The second subchamber is separated from the first subchamber and is connected with a pressure chamber. A pair of filter elements is mounted on the partition with one of the filter elements in each of the subchambers. When the element in the first subchamber becomes clogged, the partition is rotated to exchange the elements and then a piston in the pressure chamber introduces a reverse flow through the clogged element in the seconds ubchamber.

Patelited Nov.-'24, 1970 v Sheet INVENTOR A/ILS 0. ROS/767V BY #4. M, %a {3M ATTORNEYS Patented Nov. 24, 1970 Sheet 2 or 4 FIG? Sue/V010 $005155 0/ Ressun 1250 FIG. IO

INVENTOR Mas a. Rosana ATTORNEYS Patented "Nov. 24, 1970 3,543,197

Sheet 3 of 4 PUMP INVENTOR MLS 0. Ros/r64 z I ATTORNEYS Patented Nov. 24, 1970 Shaet 4 at 4 INVENTOR IY/LS 0. Ros/95M ATTORNEYS I In my aforementioned patents'a novelself-cleaning filter apparatus is disclosed in which the internal chamber of a filter housing is subdivided by -a 'rotata ble, partition member into a pair of substantiallyfluidlyseparated chamber sections includ- "ing a first chambensection having an'inletand an outlet for re'ceiving fluid to be filteredeand for'the discharge of filtered 'fluid and a second chamber section substantially fluidly :separated from the first subchamber. Alpair of filter element's mounted on the partition. are arranged with one of the filter elements disposed in-the first chamber section and the secondfilter element disposed in the second chamber section when the partition'is in one of its rotated positions. The element in fthe first chamber performs thefiltering function; while means f in the 'secondcharnber section produce a fluid surge through -the'element in"thesecond' chamber section in'order'to clean 1 the second filter element Meansiare further disclosed for auto rnatically' 'rotating'the partitionto-exchange the position of the two filter elementswhen the filter element in the'first chamber becomes clogged.v 1 The broad' pur'po'se of thepresent invention is to provide a number of improvemehts'in the aforementioned self-cleaning filter apparatus and'to disclose a fluid system in which the apparatusisincorporated.

SUMMARY- Thepreferredembodim entof the presentih vention forms the cooling system fora machine tool and includes a coolant reservoir from-which the fluid ispu mped to a filter device for -''cleaning. The clean fluid i sthen delivered'to the machine and 1 returned to the reservoir. The preferredfilt er device compartitionis rotatably mounted in an internal chamber in the prises a pair of 'semic'ylindrical'filterelements each releasably .mounted 'onoppositesides of a planar partitionm'ember. The

housing'and is movablebetwe'en a pair of rotated positions 5 180 apart. In either'of the rotated positions the partition divides the internal chambei 'into a pairof chamber sections including a filtering chamber andacleaning chamber with one of the filter ele merits beingdisposed inthe filtering chamber to separate foreignmatter'from'the fluid as it flows through the filtering' chamber and the'second filter element being l disposed in the cleaning chamber. A pressure chamber is "fluidly connected with the cleaningwc harnber and'a piston disposed in" the pressure'chzimber is operative to produce a' backwash flow through the filter element disposed in the "cleaning chamber after'the filter element has been rotated "pressure balanced by a" novel ball valve construction sothat as from the filtering-chamberin a clogged condition.

In order to collect foreign matter removed from the filter in the cleaning chamber, the conduitfrom the cleaning chamber to the reservoir discharges through a felt bag which separates the foreign matter in the backwash fluid. Thus. the backwash fluid is recovered in a fairly clean condition.

. The filter housing hasa removable sidecover which permits the filter elements to be individuallyremoved in the form of a cartridge for ease of maintenance and replaceability.

- Other advantages of the present invention'will readily occu'r to one skilled in the art towhich the invention pertains upon reference to the followingdetailed description.

DESCRIPTION OF THE DRAWINGS The description refers to the accompanying-drawings in which like reference characters refer to like parts through the several views and in which:

"FIG. 1 is-a schematic diagram of a fluid circuit illustrating the preferred embodiment of theinvention;

FIG. 2 is an elevationaI-view of the preferred filter device with parts shown schematically and parts in section for purposes of description;

FIG. 3 is an enlarged sectional view as seen along lines'3 -3 i of No. 2;

FIG. 4 is an enlarged sectional view as seenalong lines 4-4 of FIG. 2;

FIG. 5 is an enlarged sectional view-as seen along lines 5-5 of F IG. 2;

FIG. 6 is an enlarged view as seen along lines 6-6 of FIG. 4;

FIG/7 shows an enlarged fragmentary sectional view of the sealing vanes and their mounting arrangement;

' FIG. 8 X is a schematic electrical circuit showing the preferred electrical system;

FIG. 9 is an'enlarged fragmentary sectional view showing a portion of the upper wear plate in the internal chamber; and

FIG. 10'is a perspective view showing the sealing element separated from the cover and the upper wear plate.

DESCRIPTION OF THE PREFERRED EMBODIMENT Now referring to FIG. I, the preferred fluid system I0 is employed for cycling a fluid cooling agent fora machine tool (not 'shown).. The system comprises a reservoir 12 and a filter devicegenerally'indicated at 14. The filter device has an inlet l6and an outlet 18. Conduit means connect the reservoir 12 with the inlet 16 of the filtering device and pump means 22 in the conduit delivers fluid to be filtered to the inlet 16 of the It is essential that'thefluid chambers'be'fliiidly separated. whenthepartitionjis i'no'ne of its rotated positions. To achieve this fluid separationfthe partition carries ajpair of vaneelef'ments along its side edges whichare loosely mounted and the partition rotates'the vanes tilt insuch a manner as to be selfcleaning.

The cleaning chamber is fluidly connected with the coolant reservoir so thatthe backwash fluidflows through the filter "f eleme'nt andth'eritow ard the reservoir. To prevent pressure fluctuation inth'ei'system" when the partition is.-rotating and which might becausedbecause of the open center construction of the internal chamber, a valve'intheconduit between the cleaningchamberand the reservoir, automatically closes when the partition is in an intermediate position. Thus there is a continuous uninterrupted fluid flow through the device when the two filter elements are being exchanged.

filter device l4. The filtered fluid discharged from the filter device is delivered through a conduit 25 to the machine tool from which it is returned to the reservoir by return means (not shown).'

'The filter device 14 comprises housing means 24 having an internal chamber 26. A generally planar partition means 28 is rotatably mounted in the internal chamber 26 and intermittently rotated by drive'means 30 between a pair of rotated positions 180 apart in which the partition means 28 subdivides the internal chamber 26 into a pair of chamber sections which will be referred to as afiltering chamber 32 and a cleaning chamber 34. A pair of generally semicylindrical filter cartridge elements 36 and 38 are mounted on opposite sides of 'the partition means 28 so that they collectively form a substantially cylindrical filtermeans. In each of the operative rotated positions of the partition means 28, one of the filter elements is disposed in the filtering chamber 32 and the second filter element'is in the cleaning chamber 34 so that i when the partition means 28 is rotated, the two filter elements 36 and 38 exchange their relative positions. The filter element in the-filtering chamber 32is disposed intermediate the inlet 16 and theoutlet '18 so that fluid introduced into the filtering chamber 32 passes radially through the filter element and then flows through the outlet 18. As the filter element in the filtering chamber 32 assumes a clogged condition, it produces a pressure change in the system fluid. Sensing means generally indicated at 40 detect this pressure change and through suitable circuitry which will be subsequently described transmits a signal to drive means 30 which commences to rotate the clogged filter element out of the filtering chamber 32 into the cleaning chamber 34 and to rotate the clean filter element in the cleaning chamber 34 into the filtering chamber 32. This automatic exchange occurs without interrupting the continuity in the system fluid flow.

A pressure chamber 42 is fluidly connected by passage means 44 to the inner side of the filter element disposed in the cleaning chamber 32 and a piston 46 in the pressure chamber 42 is actuated after the clogged filter has been moved into the cleaning chamber 34 to produce a sudden pressure surge which causes a reverse fluid flow through the clogged filter element and removes the foreign matter collected on the outer surface of the element. The backwash'fluid flow caused by the pressure surge is directed from the filter element to a conduit means 48 which delivers the backwash fluid toward the reservoir 12. A fluid decelerator 50 mounted at the end of the conduit 48 reduces the velocity of the backwash fluid before it is discharged into a felt bag 52 which separates the foreign matter in the backwash fluid. The felt bag 52 is supported in a perforated container 54 which is mounted within the reservoir 12.

A valve 56 in the conduit 48 is normally open during the backwash cycle and is automatically closed when the partition means 28 is in a position intermediate its two rotated positions with the filtering chamber 32 and the cleaning chamber 34 i open to one another. Thus the pressure in the cleaning chamber 34 and the system is maintained until the partition means 28 has rotated to its alternate position.

Now referring to FIGS. 2-5, housing means 24 is mounted on a pedestal S8 and includes a housing member 60 in which the inlet 16 and the outlet 18 are formed and a top removable cover member 62 which is bolted on the side of the housing member 60 and upon separation from the housing member provides access to its internal components. The top cover member 62 also supports the drive means 30. A side cover member 64 is removably mounted on the side of the housing member 60 and provides access into the internal chamber 26 so that the filter elements can be individually removed from the chamber 26. The cover 64 has a central opening preferably closed by a transparent plate 66 which permits a visual observation of the interior of the housing 60. As can best be seen in FIG. 3, the housing member 60 is internally cored to form a sediment chamber 59 below the filter element 38 and on its inner side. This sediment chamber can be connected to a dump line provided with a suitable valve (not shown) for cleaning purposes. A second sediment chamber 61 is formed in the housing member 60 on the outer side of and below the filter element in the cleaning chamber 34. The sediment chamber 61 is connected by the conduit 48 to the reservoir 12.

As seen in FIG. 2, admin valve 72 connected to the opdraining the fluid from within the housing member 60.

Referring to FIG. 3, the cover 62 has a pair of passages 74 and 76. The passage 74 is in fluid communication with the inner side of the filter element disposed in the filtering chamber 32. The passage 76 provides a connection from the pressure chamber 42 to the inner side of the filter element disposed in the cleaning chamber 34.

A conduit 78 forms a fluid connection between a pump 80 and the chamber 32. The output of the pump 80 is through a conduit 81 to a valve 82 which alternately delivers clean fluid through a connection 83 to the pressure chamber or through a connection 84 to a nozzle 85 mounted in the cleaning chamber. As the clogged filter element is rotated into the cleaning chamber 34, the nozzle delivers filtered fluid against its outer surface. When the partition is in one of its rotated positions, the connection 83 provides means for filling the pressure chamber 42.

It is to be noted in FIG. 2 that the pressure chamber 42 is mounted above the cleaning chamber and is closed off by a cover member 86 which carries an inwardly directed guide rod 88 for guiding the piston 46 between its alternate positions within the pressure chamber 42. The piston 46 is movable between a retracted position wherein it abuts an annular shoulder 90 formed on the inner side of the cover 86 and an extended position wherein it abuts an enlarged portion 92 of the guide rod 88. A spring 94 disposed within the chamber biases the piston 46 toward its retracted position. ln response to a signal, pressurized fluid from a source 96 is introduced through a conduit 98 behind the piston 46 and urges the piston away from the cover 86 so that it produces a pressure wave .traveling through the passage 76 toward the inner side of the filter element disposed in the cleaning chamber 34. As the pressure wave travels through the cleaning chamber 34 it removes foreign matter on the clogged filter element and delivers the foreign matter to the conduit 48.

Because the pressure chamber 42 is mounted above the cleaning chamber 34, any air carried in the fluid has a tendency to rise upwardly and accumulate in the pressure chamber. An air bleed valve 99 provides means for drawing off the accumulation of air and is an on-off valve controlled by a solenoid 100. The solenoid 100 is operated by suitable control means so that the valve 99 is opened in the air bleed position when the filter device is in operation, however when the device is not operating the solenoid 100 closes the valve 99 to prevent draining of the fluid from the pressure chamber.

Now referring to H05. 3, 4, and 5, the partition means 28 is mounted on a vertical drive shaft 102 by a key 104 for rotation within the internal chamber 26. The lower end of the shaft is journaled in a bushing 106 and its upper end is journaled in a bushing 107 in the cover. The lower bushing 106 has an annular groove 106A connected with an axial groove 106B on the cleaning chamber side of the partition means for collecting fluid leakage from the cleaning chamber 32 which travels down between the housing 60, the bushing 106 and the partition means 28. This leakage is delivered through an opening 106C to the sediment chamber 59. The upper end of the shaft extends through the cover 62 and is drivingly coupled to'the drive means 30. Drive means 30 comprises a gear motor 108 mounted above the cover 62 on a pedestal 110.. Cam means 112 carried on the upper end of the drive shaft 102 is engageable with a switch 114 which controls the rotation of the drive shaft 102 in a manner which will be subsequently described in greater detail.

As best seen in FIGS. 4 and 7, each side edge of the partition member 28 isformed with a vertical groove 116. A retainer member 118 is mounted in each of the grooves 116 and has a vane seating groove 120 in which a pair of vanes 122 and 124 are disposed. The vanes 122 and 124 are biased outwardly by spring means 128 so that their outer edges sealingly engage a partially cylindrical side wall portion 130 of the housing which forms a part of the side wall of the internal chamber 26. The cylindrical side wall portions 130 are formed about the axis of rotation of the partition 28. As best seen in FIG. 7, the vanes 122 and 124 are loosely fitted in their grooves 120 so that they tip from side to side as the partition 28 rotates in order to release any dirt which they may collect as the partition is rotated between its alternate positions. The

' two vanes are attached to the retainer by a pin 132. The vane 124 is of rubber and the vane 122 is of metal.

The retainer 118 has a passage 134 connected to a pair of short passages 136 and 138 in the partition 28. The passage 136 provides a fluid connection between the passage 134 and the filtering chamber 32 while the passage 138 provides a fluid connection between the passage 134 and the cleaning chamber 34. A ball 140 is disposed in the passage 134 and moves between opposite ends of the passage 134 depending on the pressure differential existing between the cleaning chamber 34 and the filtering chamber 32. A short passage 142 connects the passage 134 to the vane seating groove 120 so that the pressure existing within the passage 134 is reflected in the groove 120 and behind the vanes. The two vanes 122 and 124 are formed with a pair of opposed grooves 144 on their face-to-face surfaces so that the grooves l44reflect'pressure changes in the passage 134 at the outer tips of the vanes 122 and 124. Thus the ball 140 acts as a valve which assumes a position dependent on the chamber having the greater fluid pressure. The vanes 122 and .124 are essentially pressure balanced by the pressure existing behind the two vanes in the groove 120 which always reflects the pressure in the chamber having-the greater pressure as the valve moves back and forth in response to changes in thepressure differential existing betweenjthe filtering chamber 32 and the cleaning chamber 34.

Now referring to FIGS. 3, 4, and 7, eachof the filter elements 36 and 38 is:in the form of acartridge which can be easily removedthrough the side cover 64.'Each filter element comprisesanouter perforated generally semicylindrical shell section 146, an inner generally semicylindrical section 148 and a removable mesh element l50'having a generally pleated configuration. The outer shell 146 is joined to the inner shell l4 8 with the mesh element 150 being disposed in a housing formed by the two shellelements The mesh element 150 is attached by an elongated .clipelement 152 having. a J-shaped cross section and attached to the side edgeof the mesh element 150, a second elongated clip 154 having a J-shaped cross section fixedly attached to the inner shell 148 and an elongated retainer clip- 156 having a C-shaped cross section which is joined to the-clips 152 and 154 by a sliding motion in a direction parallel to their longitudinal edges. The filter element 36 and thefilter element 38-are similar to one another and each attached by threaded fasteners 158t'o the retainer 118, Thus'each filter elementcan beremoved through the access opening providedby removal of cover 64 and the mesh element 150iseparated fromthe two shell sections by disen gaging the clip means 156 from the two clips 152 and 154. The mesh element 150 can-then beexpanded; cleaned and then quickly and easily reinstalled between the shell elements 146 and 148.

Referring to FIGS. 3, 9 and 10, each filter element is sandwiched'between an upper ring segment 160and a lower ring segment 162. The lower ring segment 162 rides on a lower wear plate 164 mounted in'the bottom'of the internal chamber 26. An upperwear plate 166 is disposed betweenthe cover 62 and the two filter elements. The wear plate 166 is fixed against rotation bya pin (not shown) and biased down against the filter elements by spring means 168: The downward bias of the spring means is assisted by a clearance between the circumferential edge of the wear plate 166 and the housing 62 as at 168Afand a clearance between the upper surface wear plate 166 and the housing 62' as at 16813 that allows fluid pressure from within the chamber to act downwardly on the wear plate.

The housing62 has an elongated groove 170 above the wear plate. An elongated sealing element 172 is seated in the groove 170 and provides afluid'seal between the chambers 32 and 34 whenever the partition means 28 is'in one of its rotated positions.

Referring to FIGS. 4 and 6, sensing means 40 detect a fluid pressure change occurring'atthe inlet 16 caused by the filter element in the filtering chamber'32 assuming a clogged condi tion. Sensing means 40 comprises a substantially cylindrical chamber 174 having an opening 176 adjacent the inlet 16 and another openingl7 8(.best seenin FlG. l) which connects with the outlet 18. A cap 180 is mounted at one end of the chamber 174' andsupports an inwardly directed guide rod 182 which extendstowardfthe opening 176. A cup-shaped piston member 184 issealingly slidably mounted on the rod in the opening 176. Thus-the outer'surface'of the piston 184 is exposed to the pressure in the inlet 16 and the inner surface of the piston 184 is exposed to the pressure at the outlet 18 so that the piston moves to positions corresponding to the pressure differential between the inletand outlet.

The rod 182 has an enlarged end"186which limits the motion of the piston 1 84 away from the cap 180. A spring 188 in the chamber 174 biases the piston 184 away from the cap 180 and is chosen of a selectedistrength so that the piston commences to move when a predetermined pressure differential is created across the inlet by a clogged filter element.

A piston 184 has a slotted pilot portion 190 bearing against a crank am 192 having a regular longitudinal twist. The crank arm 192 is supported for rotation about its longitudinal axis on the innerend of a shaft 194 which is journaled in the cap and extends exteriorly of the cap 180. As best seen in FIG. 6 the outer end of the shaft 194 carries a cam 196 and a pointer 198. As the piston 184 is moved by the changing pressure differential against the bias of the spring-188, the pilot portion causes the crank arm 192 and the shaft 194 to rotate thereby causing the pointer to traverse a legend plate 200 mounted on the cap 180. Thepointer 198 and the legend plate 200 cooperate to visually indicate the filtering condition of the filter element disposed in the filtering chamber 32.

A normally open plunger type switch 202 is mounted on the cap l80'and arranged such that when the cam 196 rotates clockwise as the filter element disposed in the filtering chamber 32 becomes clogged, the switch 202 energizes the gear motor 108 which commences to rotate the drive shaft 102.

Referring to FIGS. 1 and 8, the preferred electrical circuit shows that the switches 202 and. 114 are connected in series with the motor 108 and the coil 204 of the starter relay for the motor 108. Normally opencontacts 206 of the starter relay coil shut the switch 202. The normally open switch 202 is closed upon an increased pressure differential across the filter element disposed in the filtering chamber 32 so that the relay coil 204 becomes energized which in turn energizes the motor 108. locks in the contacts 206 and closesa normally opened solenoid switch which is adapted to close the valve 56 in the backwash conduit'48.

As the drive shaft 102 commences to rotate, the clean filter element in the cleaning chamber 34 is rotated into the filtering chamber 32 with the pressure differential returning to its normal level so that the switch 202 resumes its normally opened condition. The cam 112 carried by the drive shaft engages the normally closed switch 114 to momentarily move it to an opened position and thus deenergize the motor 108, the relay 206 and the solenoid switch 208. As the motor 108, through inertia, moves one of a pair of lobes of the cam 112 past the switch 114 so that it again assumes its closed condition, the circuit remains open until the next cycle is initiated by a change in the pressure differential across the filter element in the filtering chamber 32. A solenoid valve 210 is then triggered to introduce pressurized fluid, such as compressed air, from the source 96 behind the piston 46. It is to be understood that the electrical circuit is described in its simplest terms and is for illustrative purposes only, and that it would be obvious to one skilled in the art that a variety of electrical circuits could be used to perform the aforementioned sequence of operations.

It is to be understood that l have described an improved fluid system having a self-cleaning filtering device for cleaning the coolant supplied to a machine tool with pressure-actuated means for automatically exchanging the clogged filter with a clean filter. The preferred filter device employs pressure balance vane means for sealing the two chambers one from the other. The'filter element exchange occurs without interrupting the flow of fluid'being delivered to the machine. Each filter element can be readily removed from the housing.

[Claim 1. A fluid system, comprising:

a. filter-housing means having an internal chamber, an inlet for receiving fluid into said internal chamber and a pair of outlets for the removal of fluid from said internal chamber;

b. partition means; I

c. means for mounting said partition means in said internal chamber for 'rotation between predetermined rotated positions wherein said partition means subdivides said internal chamber into a plurality of chamber sections including a first chamber section in fluid communication with said inlet and a first of said outlets, and a second chamber section, separate from said first chamber section, and in fluid communication with the second of said outlets;

. a pair of filter elements carried by said partition means with one of said filter elements disposed in each of said chamber sections, the filter element in said first chamber section being disposed in the path of fluid delivered through said inlet and toward the first of said outlets so that the fluid flows in a first direction through said filter elements;

. a fluid reservoir;

means for delivering fluid from said reservoir to the inlet of said filter housing for filtering by the filter element in said first chamber section;

. a pressure chamber fluidly connected with said second chamber section;

. means for introducing fluid into said pressure chamber;

. means in said pressure chamber for producing a fluid pressure surge from said pressure chamber in a reverse direction through the filter element in said second chamber section and toward the second of said outlets to clean the filter element in said second chamber section;

. means connecting the second of said outlets with said reservoir for the transfer of the cleaning fluid to said reservoir from said second chamber section; and

k. fluid-filtering means disposed within said connecting means whereby said cleaning fluid is delivered to said reservoir in a cleaned condition.

2. A system as defined in claim 1, wherein said last-mentioned filtering means comprises a fluid pervious bag and means for discharging the fluid from said second chamber section into said bag.

3. A system as defined in claim 1, wherein said connecting means comprises a conduit and including decelerator means in said conduit downstream of said second chamber section for reducing the energy of the fluid pressure surge traveling through said conduit from said pressure chamber through said second chamber.

4. A system as defined in claim 1, wherein said last-mentioned means comprises a conduit and including valve means in said conduit, and means for closing said valve means when said partition means is being rotated between said predetermined rotated positions to close fluid communication between said internal chamber and said reservoir through said conduit.

5. A system as defined in claim 1, including means for sensing a differential pressure change in the fluid flowing through said first chamber section caused by the filter element in said first chamber section assuming a clogged condition, and drive means responsive to said sensing means for rotating said partition means between rotated positions to rotate a clean filter element into said first chamber section and to rotate the clogged element into said second chamber section.

6. A system as defined in claim 1, wherein said housing means has a removable cover providing access into said internal chamber and permitting the individual removal of said filter elements from said internal chamber.

7. A filter device for separating foreign matter from a moving, fluid medium, comprising:

a. a housing having internal walls defining an internal chamber, an inlet for receiving fluid into said internal chamber and an outlet for the discharge of fluid from said internal chamber;

b. a carrier structure mounted in said internal chamber for rotation between predetermined rotated positions;

c. partition means on said carrier structure for subdividing said internal chamber into a plurality of separated chamber sections when said carrier structure is in one of said predetermined rotated positions including a first chamber section fluidly communicating with said inlet and said outlet and a second chamber section separated from said first chamber section;

d. vane means mounted on the edge of said partition means for engaging the walls of said internal chamber to provide a seal between said first and second chamber sections, said vane means having pressure-responsive surfaces;

. passage means in said partition means for connecting said first and second chamber sections with said pressureresponsive surfaces;

f. valve means in said passage means for opening communication between said pressure-responsive surfaces and the chamber section having the greater fluid pressure and closing communication between said pressure-responsive surfaces and the chamber section having the lesser fluid pressure;

a plurality of filter elements;

. means for mounting a first of said filter elements on said carrier structure in said first chamber section intermediate said inlet and said outlet so that fluid introduced through said inlet flows through said first filter element in a first direction, and a second of said filter elements on said carrier structure in said second chamber section when said carrier structure is in a first ofsaid rotated positions; and

. means for rotating said carrier structure from the first of said rotated positions to the second of said rotated positions when the filter element in the first chamber section becomes clogged so as to rotate the clogged filter element into the second chamber section and to rotate a relatively clean filter element into said first chamber section.

8. A fluid filter as defined in claim 7, wherein said housing has cylindrical wall sections forming said chamberabout the axis of rotation of said carrier structureand engageable with said vane means when said carrier structure is in one of said predetermined rotated positions.

9. A fluid filter as defined in claim 7, including a cover removably mounted on said housing means to form the top wall of said internal chamber, a wear plate mounted between said partition means and said cover, and means biasing said wear plate downwardly toward said partition means.

10. A fluid filter as defined in claim 7, including conduit means providing a connection from the downstream side of the filter element in said first chamber section to the innerside of the filter element disposed in said second chamber section and pump means in said conduit means for delivering filtered fluid from said first chamber section to said second chamber section.

11. A fluid filter as defined in claim 7, wherein said first and second chamber sections are open to one another when said partition means is in an intermediate position between predetermined rotated positions.

12. A fluid filter device as defined in claim 7, including means for providing a continuous flow of filtered fluid from the downstream side of the filter element disposed in said first chamber section to the outer side of the filter disposed in the second chamber section when said partition means are in a predetermined rotated position.

13. A fluid filter as defined in claim 7, and including said housing means having an opening, a cover removably mounted on said housing means to close said opening and to form the top wall of said internal chamber, said filter elements and said carrier structure being removable from said chamber through said opening upon removal of said cover.

14. A fluid filter as defined in claim 7, including a cover removably mounted on said housing means to form the top wall of said internal chamber, a wear plate mounted between said partition means and said cover and means biasing said wear plate downwardly at a predetermined force towards said partition means.

15. A fluid filter as defined in claim 7, wherein said housing means has a removable cover forming a wall of said internal chamber and providing means for individually removing each of said filter elements from said internal chamber.

16. A fluid filter as defined in claim 15, wherein each of said filter elements, comprises a pair of fluid pervious semicylindrical shell elements joined together along their side edges to form a cartridge assembly, a flexible filter member disposed in said cartridge assembly and clip means releasably mounting said flexible filter member in said cartridge housing,

17. A fluid filter as defined in claim 7, wherein said housing has a pressure chamber above'the filter element in said second chamber section so thatair carried in the fluid passing through said internal chamber tends to collect in said pressure chamber.

18. A filter device as defined in claim 17, including means on said pressure chamber-for bleeding the air collected in said pressure chamber.

19. A fluidffilter as defined in claim 18, wherein said bleed means comprises a valve having an open condition for bleedingair from said pressure chamber when the fluid in said pressure chamber is underipressure and a closed condition when the fluid is not flowing through the filter device so as to prevent saidpressure chamber from being drained.

20. A fluid filter as defined in claim 7, wherein said housing has a sediment chamber in said second chamber section and below the innerside of the filter element disposed in said second chamber section when the partition means is in a predetermined'rotated position.

21. A filter deviceasdefined in claim 20, wherein said housing means has a second outer sediment chamber in said second chamber section on the outer side and below the filter element disposed insaid second chamber section.

22. A fluid filter as defined in claim 20, including conduit means in said housing for removing sediment collected in said outer sediment chamber and valve means for closing said conduit meanswhensaid partition means is in an intermediate position between said predetermined rotated positions.

23. A fluid filter device as defined in claim 7, wherein the side edges of said partition means are formed with groove means facing the walls of said internal chamber and including vane means engaged with said walls and mounted in said grooves so as to tip relative to said partition means as said partition means rotates between rotated positions.

24. A fluid filter device as defined in claim 23, wherein said vane means comprise a pair of elongated vane members mounted in face-to-face relationship in said groove means with the base disposed in said groove means and tips engaged with the walls of said internal chamber and including slot means formed between said vanes from their base to their tip.

25. A filter device for separating foreign matter from a moving fluid, comprising:

a. a housing having internal walls defining an internal chamber, an inlet for receiving fluid into said internal chamber and an outlet for the discharge of fluid from said internal chamber;

b. a carrier structure mounted in said internal chamber for rotation between predetermined rotated positions;

c. partition means'on said carrier structure for subdividing said internal chamber into a plurality of separated chamber sections when'said carrier structure is in one of said predetermined rotated positions including a first chamber section fluidly communicating with said inlet and said outlet and a second chamber section separated from said first chamber section;

d. a wear plate mounted between a first wall of said internal chamber and said partition means;

e. means biasing said wear plate against said partition means;

seal means disposed between said first wall and said wear plate to provide a fluid seal between said first and second chamber sections when said partition means is in one of said rotated positions;

. a plurality of filter elements;

. means for mounting a first of said filter elements on said carrier structure in said first chamber section intermediate said inlet and said outlet so that fluid introduced through said inlet flows through said first filter element in a first direction, and a second of said filter elements on LII said carrier structure in said second chamber section when said carrier structure is in a first of said rotated positions; and

i. means for rotating said carrier structure from the first of said rotated positions to the second of said rotated posi tions when the filter element in the first chamber section becomes clogged so as to rotate the clogged filter element into the second chamber section and to rotate a relatively clean filter element into said first chamber section.

26. A fluid filter as defined in claim 25, including means for introducing fluid from said chamber sections between said first wall and said wear plate so that said wear plate is fluid pressure balanced.

27. A fluid filter as defined in claim 25, wherein said seal means comprises a groove formed in said first wall facing said wear plate and extending the width of said wall and an elongated seal element disposed in said groove and engaged with said wear plate to form a fluid tight seal between said first wall and said wear plate.

28. A fluid filter as defined in claim 25, wherein said carrier structure has a shaft and including bushing means mounted in said housing for journaling the end of said shaft; said bushing means having an annular groove axially spaced from said chamber sections for collecting fluid leakage between said bushing and said housing from one of said chamber sections and passage means for delivering the fluid leakage from said annular groove to a second of said chamber sections.

29. A fluid filter as defined in claim 28, wherein said annular groove collects fluid leakage from said first chamber section, and said second chamber section has a. sediment chamber, and said passage means connects said annular groove and said sediment chamber.

30. A fluid system, comprising:

filter-housing means having an internal chamber, an inlet for receiving fluid into said internal chamber and a pair of outlets for the removal of fluid from said internal chamber;

partition means and means for mounting said partition means in said internal chamber for rotation between predetermined rotated positions wherein said partition means subdivides said internal chamber into a plurality of chamber sections including a first chamber section in fluid communication with said inlet and a first of said outlets, and a second chamber section separate from said first chamber section and in fluid communication with the second of said outlets;

a pair of filter elements carried by said partition means with one of said filter elements disposed in each of said chamber sections, the filter element in said first chamber section being disposed in the path of fluid delivered through said inlet and toward the first of said outlets so that the fluid flows in a first direction through said filter elements;

a fluid reservoir and means for delivering fluid from said reservoir to the inlet of said filter housing for filtering by the filter element in said first filter chamber section;

a pressure chamber fluidly connected with said second chamber section and means for introducing fluid into said pressure chamber;

means in said pressure chamber for producing a fluid pressure surge from said pressure chamber in a reverse direction through the filter element in said second chamber section and toward the second of said outlets to clean the filterelement in said second chamber section;

means connecting the second of said outlets with said reservoir forthe transfer of the cleaning fluid to said reservoir from said second chamber section; and

said partition means comprising a generally planar partition member mounted in said internal chamber for rotation, vane means associated with each side edge of said partition member and means mounting said vane means on said side edges to engage the sidewalls of said internal chamber when said partition member is in said predetermined rotated positions.

31. A system as defined in claim 30, wherein said vane means comprise a pair of similarly shaped vane elements, one of said vane elements being formed of metal and the second of said vane elements being formed of a resilient material.

32. A system as defined in claim 30, wherein said partition member has an elongated groove in each of its side edges facing the sidewall of said internal chamber when said partition member is in said rotated positions, and said vane means comprises a pair of vane elements having sealing edges and associated with each side edge, means mounting said vane elements in their respective grooves with their sealing edges engaging the sidewalls of said internal chamber, and spring bias means in said grooves resiliently urging said vane elements against the sidewalls of said internal chamber.

33. A system as defined in claim 32, wherein said pair of vanes are disposed in side-by-side relationship in their respective grooves, the total thickness of said vanes being less than the width of their respective grooves so that each pair of.vanes tip as said partition member is rotated in said internal chamber.

34. A system as defined in claim 32, including means for producing a pressure differential in the chamber sections on the opposite sides of said partition member,fluid passage means connected with the grooves behind said vanes and pressure-responsive means for opening a connection between the chamber section having the higher fluid pressure and said grooves.

35. A system as defined in claim 34, wherein said pressureresponsive means comprise a ball disposed in said passage means with opposite sides exposed to the fluid pressure in opposite chamber sections so that said ball moves in said passage means in a direction away from the chamber section with the greater pressure to a position opening fluid communication with the chamber with the greater pressure and said grooves and closing fluid communication between the chamber with the lesser pressure and said grooves so that the fluid from the chamber section with a greater fluid pressure acts behind said vanes to urge them into sealing engagement with the sidewalls of said internal chamber.

36. A fluid system, comprising:

filter-housing means having an internal chamber, an inlet for receiving fluid into said internal chamber and a pair of outlets for the removal of fluid from said internal chamber;

partition means and means for mounting said partition means in said internal chamber for rotation between predetermined rotated positions wherein said partition means subdivides said internal chamber into a plurality of chamber sections including a first chamber section in fluid communication with said inlet and a first of said outlets, and a second chamber section separate from said first chamber section and in fluid communication with the second of said outlets;

a pair of filter elements carried by said partition means with one of said filter elements disposed in each of said chamber sections, the filter element in said first chamber section being disposed in the path of fluid delivered through said inlet and toward the first of said outlets so that the fluid flows in a first direction through said filter elements;

a fluid reservoir and means for delivering fluid from said reservoir to the inlet of said filter housing for filtering by the filter element in said first filter chamber section;

a pressure chamber fluidly connected with said second chamber section and means for introducing fluid into said pressure chamber;

means in said pressure chamber for producing a fluid pressure surge from said pressure chamber in a reverse direction through the filter element in said second chamber section and toward the second of said outlets to clean the filter element in said second chamber section;

means connecting the second of said outlets with said reservoir for the transfer of the cleaning fluid to said reservoir from said second chamber section; and

said means for introducing fluid into said pressure chamber comprising a fluid connection from the downstream side of the filter element in said first chamber section to said pressure chamber so that filter fluid is introduced into said pressure chamber.

37. A fluid system, comprising:

filter-housing means having an internal chamber, an inlet for receiving fluid into said internal chamber and a pair of outlets for the removal of fluid from said internal chamber; and

partition means and means for mounting said partition means in said internal chamber for rotation between predetermined rotated positions wherein said partition means subdivides said internal chamber into a plurality of chamber sections including a first chamber section in fluid communication with said inlet and a first of said outlets, and a second chamber section separate from said first chamber section and in fluid communication with the second of said outlets;

a pair of filter elements carried by said partition means with one of said filter elements disposed in each of said chamber sections, the filter element in said first chamber section being disposed in the path of fluid delivered through said inlet and toward the first of said outlets so that the fluid flows in a first direction through said filter elements;

a fluid reservoir and means for delivering fluid from said reservoir to the inlet of said filter housing for filtering by the filter element in said first filter chamber section;

a pressure chamber fluidly connected with said second chamber section and means for introducing fluid into said pressure chamber;

means in said pressure chamber for producing a fluid pressure surge from said pressure chamber in a reverse direction through the filter element in said second chamber section and toward the second of said outlets to clean the filter element in said second chamber section;

means connecting the second of said outlets with said reservoir for the transfer of the cleaning fluid to said reservoir from said second chamber section;

means for rotating said partition between said rotated posi-' tions when the filter element in said first chamber section becomes clogged so as to rotate the clogged element into said second chamber section;

nozzle means for directing fluid against the clogged side of the clogged filter element as it is rotated from said first chamber section into said second chamber section; and

a fluid connection from the downstream side of the filter element in said first chamber section to said nozzle means for delivering filtered fluid to said nozzle means.

38. A filter device for separating foreign matter from a moving fluid medium, comprising, housing means having a fluid chamber and having sidewalls forming a portion ofa cylinder, said housing having an inlet for receiving fluid to be filtered and an outlet for filter fluid each fluidly connected with said filter chamber, a carrier structure and means rotatably mounting said carrier structure in said fluid chamber for rotation between operative positions about the axis of the cylinder defined by said sidewalls, a partition structure carried by said carrier structure and including resilient vane members at opposite ends of the partition structure and engaging the sidewalls of said fluid chamber at the operative posltons of said carrier structure to subdivide said chamber into a plurality of subchambers including a first subchamber fluidly connecting the inlet and the outlet of said housing means and a second subchamber normally fluidly separated from said first subchamber and from said inlet and said outlet, a plurality of similarly shaped filter elements mounted on said carrier structure, each of said filter elements having a partially cylindrical shape so that said filter elements collectively form a substantially cylindrical means having an axis coinciding with the axis of rotation of said carrier structure, at least one of said filter elements being disposed in said first subchamber so that unfilsaid filter elements being disposed in said second subchamber when said carrier structure is in an operative position, means operable upon being actuated to produce a backwash through the clogged filter element in said second subchamber in a radial direction opposite to said first radial direction to clean said clogged filter elementja reservoir connected with said second subchamber and fluid filtering means disposed intermediate said second, subchamber and said reservoir whereby the sidewalls of 'said fluid chamber at the operative positions of said carrier structure to subdivide said chamber into a plurali- -ty of subchambers including a-first subchamber fluidly connecting the inlet and the outlet ofsaid housing means and a second subchamber normally fluidly separated from said first subchamber and from said inlet and said outlet, a plurality of similarly shaped filter elements mounted on said carrier structure, each of said filter elements having a partially cylindrical shape so that said filterelements collectively form a substanbackwashed fluid. is returned to said reservoir in a cleaned ing said carrier structure in said fluid chamber for rotation between operative positions about theaxis of the cylinder defined by said sidewalls, a partition structure carried by said carrier structure and including resilient vane members at op posite ends of the partition structure and engaging the tially cylindrical means having an axis coinciding with the axis of rotation of said carrier structure, at least one of said filter elements being disposed in said first subchamber so that unfiltered fluid is delivered in. a first radial direction to said filter elements for separation of foreign matter and the second of said filter elements beingdisposed in said second subchamber when said carrier structure is in an operative position, means operable upon being actuated to produce a backwash through the clogged filter element in said second subchamber in a radial direction opposite to said first radial direction to clean said clogged filter element, and means connected with the upper portion of said first subchamber for removal of air therefrom. 

